1. Field of the Invention (Technical Field)
Embodiments of the present invention relate to the general field of electrosurgical generators that are used to power devices, such as instrument probes, developed for use in surgical and medical procedures.
2. Description of Related Art
The use of electrosurgical instruments in various types of surgical procedures has become widespread and generally consists of a system whereby a treatment device probe is connected to an electrosurgical generator. The device probe delivers the energy from the electrosurgical generator to the tissue treatment site via electrodes to provide a therapeutic effect. Device probe and electrosurgical generator architecture have been developed for particular therapeutic needs, depending upon, for example, the goals of treatment, the tissue type to be treated, and the treatment environment. Most commonly, electrosurgical generators consist of either monopolar or bipolar configurations, or both, which have become well known in the art. Likewise, either monopolar or bipolar treatment device probes have been developed to connect to those types of electrosurgical generators via an electrosurgical generator output port, either monopolar or bipolar, respectively. Active (or working) and return (reference) electrodes then function in a variety of ways based upon, for example, configuration, architecture, and connection to the electrosurgical generator. In this manner, either a monopolar or bipolar output portal, or both, exists on the electrosurgical generator into which the device probe, either a monopolar or bipolar device respectively, is connected. A monopolar device is connected to a monopolar output portal on the electrosurgical generator and, likewise, a bipolar device is connected to a bipolar output portal on the electrosurgical generator. Typically, feedback from the treatment site is then managed by way of the relevant monopolar or bipolar circuitry within the electrosurgical generator and between the device probe electrodes that are connected to the electrosurgical generator accordingly.
More generally, and to date, the electrosurgical industry has provided a wide variety of products geared toward this single-mode of operation from specific electrosurgical generator output portals (monopolar or bipolar). Within this design limitation, specific control mechanisms, circuitry, and software algorithms have been developed and applied to the management of the variable feedback that can be obtained from a single portal output for any given device. Since device probe geometries tend to be more fixed than variable with respect to monopolar or bipolar configuration, the electrical signature of a given device is commonly treated as a constant within the context of an overall surgical procedure; i.e. a monopolar or a bipolar device.
The direct result of this prior art has been to provide specific output portals for the most common types of electrosurgery; those being monopolar and bipolar. Each of these output portals is designed to provide specific controls that limit the amount of maximum current, voltage or time-based modulations of current and voltage in response to the variations in factors at the treatment site. The result is intended to control the overall output to the active (working) end of the attached device probe and keep its general state of operation within a specified “safe-range” to avoid excessive heat, current, or current density from forming within the surgical site or elsewhere within the patient at the time of treatment.
Such circuitry for this monopolar or bipolar configured output portals is contained within the physical confines of the electrosurgical generator enclosure itself, proximal to the connection of the device probe, and is coupled to an electronic and software controller that monitors said variables and continually checks their time-varying values against preset performance limits. When these performance limits are exceeded, the controlling algorithm forces a safety trip, thus shutting down the primary RF-power output to the working end of the attached device. The specifics of these predefined software controlled trip points is that they are based on the electro physical constraints electrosurgical generator manufacturers have placed on the output portals, which as previously discussed, are configuration specific (monopolar or bipolar). Thus, the physical spacing of primary components such as the active (working) and return (reference) electrodes plays a paramount role in what those specific characteristics are that govern said trip points for safety control.
The overall industry result from this configuration model is a trajectory of “silo” thinking for each specific electrosurgical output portal, meaning that devices have been optimized for either the monopolar output portal or bipolar output portal of electrosurgical generators. Traditional thinking of the prior art has been that there is no advantage in shrinking the physical space of a given portals output for a specific mode, meaning that a monopolar procedure that involves a separated ground pad, typically placed at a great distance from the surgical site, has been thought to need such separation to operate effectively and that such separation is exactly why the procedure has been named “mono” polar as the electrical poles are separated by such large relative distances that only a single pole is effectively at work within the surgical site. On the other end of the spectrum is the “bi” polar method of electrosurgery which has drawn its name from the physical basis of active (working) and return (reference) electrode proximities to one and other. Thus, to date industry has remained ensconced in fixed paradigm of one treatment device probe configuration per output port of the electrosurgical generator; i.e. monopolar device to monopolar output port and bipolar device to bipolar output port.